In the past thirty years, well in excess of one hundred patents have been granted for variations on the sawhorse. Many of these patents have been focused on the addition of features which enhance the utility of the device, while others have been focused on methods for folding or collapsing the device.
The sawhorses of the prior art such as those marketed by GOLDEN STATE MOBILE HOME SERVICES, and which are used to support heavy structures, tend to lack lateral stability when a substantial force is applied to the side of the sawhorse. The horizontal component of such force would cause the sawhorse to bend sideways, thus forming a deviation angle with the vertical plane.
Even a small deviation from the vertical plane could prove to be detrimental to the stability of the structure, especially when the supported weight is heavy. In which case, the vertical weight of the structure exerts a distorting torque proportional to the sine of the deviation angle. Such distorting torque increases the deviation angle, which causes an increment in the distorting component of the applied torque, until the sawhorse and the supported structure collapse.
Another disadvantage of the existing devices is that they afford a very limited degree of adjustment. When the ground on which the sawhorses are to be installed is not perfectly leveled, the compensation is primitively made by placing wooden pads under the sawhorses.
Even though the cross beam between the lateral supports could provide coarse vertical adjustments, the beam could not deviate from the horizontal position for fear of causing an incremental torque which forces the collapse of the sawhorse, as described above.
Wherefore, the existing devices could not offer refined adjustments. In the event the soil movement (such as an earthquake) causes the cross beam to deviate from its horizontal position, while the sawhorses are supporting a heavy structure such as a mobile home, the homeowner has to have the mobile home lifted while he inserts the wooden pads under the sawhorses, in order to compensate for the soil movement. This would be inconviently achieved at a considerable expense.
There is thus a need to construct an improved sawhorse with greater strength, rigidity and stability, and with a more flexible and variable capacity for adjustment, than the existing sawhorse.